Unmanned autonomous vehicles (UAVs) have a maximum travel range due to a finite supply of onboard power. While refueling stations (e.g., charging stations) may be provided to extend the travel range of the UAV, such refueling stations may not be readily available for all parts of a long-range course. In addition, reaching the refueling stations may take too long, causing the UAV to be late in reaching its destination. Although onboard energy harvesting systems (e.g., solar cells) may be provided, propulsion systems generally consume energy much faster than can be harvested. In addition, inclement weather en-route to a destination may prevent onboard energy harvesting systems from harvesting enough energy to complete a course.